Devices of this type (e.g., German Offenlegungsschrift 19 09 130) are often used in connection with hydraulic units. In such uses, a filter element or several filter elements are incorporated in the associated container, for instance, in a tank for hydraulic fluid, as a return filter for the hydraulic fluid.
In the case of the filter elements, there can be a question of the need to change the filter cartridges when they become polluted. In addition, a pollution indicator device can be present in the assembly. Such devices can also be used advantageously, for instance, with the fuel or lubricant filters which are provided specifically for in-tank installation.
In the case of known devices of the this type, difficulties often arise while they are in operation. This is especially the case where the relevant fluid flows through the filter element at a relatively high flowthrough rate. As a result of the high flow forces, which thus engage on the filter element, undesirable changes in the position of the filter element relative to its housing often arise. Upon such position changes, among other things, even the seal between the filter element and its seat on the housing part can be influenced or damaged.